Piston ring



April 1930- J. J. HOWARD 1,752,848

PISTON RING Filed Jan. 16. 1928 ATTORNEY Patented Apr. 1, 1930 i UNITED STATES PATENT OFFICE JAMES J'. HOWARD, OF STAMFORD, CONNECTICUT rrsron RING Application filed January 16, 1928. Serial No. 247,131.

This invention is an improvement; in piston Fig. 4 is a plan view of the ring as it aprings, and more particularly in sectional pears when inserted in the cylinder. rings. Fig. 5 is a perspective view of the ring.

The usual construction of piston ring is a In the present embodiment of the inven- 5 split ring, with the ends beveled or rabbeted tion, the ring which is of the usual suitable or both, and the ring is placed by spreading it material, consists of similar sections 1, each of so that it will slip over the piston and into the which is of somewhat greater length than a e, half circle, and the ends of each section are This type of ring is only applicable to rings rabbeted as shown at 2, so that the ends of 10 of relatively small cross section. When the the sections may lap upon each other, the ring is thick axially, or wide radially, it is imdepth of the rabbets being substantially half practicable to place it in this manner, as it the axial width of the ring. will snap under the strain of spreading. Fur- The sections are similar, and the ends are thermore, distortion results due to the spreadbeveled as are also the shoulders formed at the 15 ing,and the ring when placed does not fit the inner ends of the rabbets, so that the end of cylinder exactly, and cutting results. each section fits the shoulder of the other see- One of the primary objects of the present tion, the beveled end and the beveled shoulinvention is the provision of a ring composed der being indicated at 3 and 4: respectively.

of similar sections, whereby to enable the po- The improved ring is constructed by first sitioning of the ring in the groove of the pisturning a continuous ring about an eighth of ton without any spreading operation and with an inch greater in diameter than the cylinder no consequent distortion of the ring. bore, into which the ring is designed to fit. As Another object is the provision of a form of for instance, in a three and three-quarter inch ring suitable for use with light or heavy macylinder, the ring would be turned to three terial, involving no liability to breakage or and seven-eighths inch external diameter. It 7 distortion in the placing thereof. is then cut in half by rabbeting, which results Another object is the provision of a form in a ring in two similar sections, each of which of ring, which when inserted will fit the cylinis on an arc of slightly greater radius than der exactly, and at every point in the circumthat of thecylinder.

ference of the ring, thereby to provide a per- A number of rings so constructed, and with feet seal, without undue wear on the cyllnder the sections assembled, is now inserted in a wall. shell 5 having an internal diameter of one With these and other objects in view the thirty-second of an inch larger than the bore invention consists in the construction and of the cylinder for which the ring is designed. novel combination of parts fully described The insertion of the r 1ng.sect1ons in the shell hereinafter, illustrated in the accompanying P em n er en lon, Slnce there s a dlfdrawings, and pointed out in the claims apference of three thirty-seconds of an lnch bepended hereto, it being understood that varitween the Internal dlametel Q the Shell i 40 ous changes in the form, proportion, size d the external dlameter of the rlng, and in this minor details of construction within the scope of the claims,-may be resorted to without deer and are forced out of the Shell in a be Partmg from h splrlt i the mventlon' Aiterwards the rin s are turned to the s ia e In the drawings iormmg a part hereot of the cylinderboref 45 t 1 P t Vlew of h Improved F When completed, and released from the lz 2 9 the 11118 2 2 9 washers, the rings assume a slightly oval g- 1S an end Vflew of h Shell 1n hl cross section, the long axis being between the h sectlons of the g are aesembledfor laps, and between the centers of the rabbets ternal turning, and wlth a ring abuttlng the at each side of the ring. When the improved end thereof. ring is inserted in a cylinder, the ring as a by any suitab e means, as for instance washcondition the are clamped together axially whole assumes an exact circular shape, touchlength to the length of the internal circuming the cylinder wall at every point in its cirference of the cylinder for which it is decumference. Because of the shape of the ring signed, and being slightly elliptical in conand its resiliency, compression at the ends tour.

of the long axis decreases the radius in this Signed at Stamford, in the county of Fairdimension, with a consequent maximum of field and State of Connecticut, this 26th day increase in a direction of right angles thereto, of November, A. D. 1927.

and an increase gradually diminishing from midway of the section to the ends.

It is obvious that the two piece ring can be made in any reasonable thickness, and in any reasonable or practical width, and it can be placed in a cylinder without liability of breakage, and without liability to any permanent distortion. With the improved ring there is a seal as perfect as possible, and the wear of the cylinder is uniform.

Because of the, waste in material in forming the rabbets, that is in separating the ring into two parts, it will probably be advisable in practice to make the improved ring out of two rings instead of out of one, that is a continuous ring for each section. In this case it will be obvious that the ring will be constructed by first turning two continuous rings, and cuttlng each to shape.

What is claimed as new is 1. A piston ring having an external circumference corresponding in length to the 30- length'of the internal circumference of the cylinder for which it is designed, slightly elliptical in contour, and composed of similar sections, lapping at their ends, the laps being at the ends of the long axis.

2. A piston ring having an external circumference corresponding in length to the length of the internal circumference of the cylinder for which it is designed and slightly elliptical Y Y in contour, the ring composed of similar sections, the ends of the sections rabbeted in the plane of the ring to lap, the ends of the iong axis of the ring being midway of the aps.

3. A piston ring composed of similar sections rabbeted to lap at their ends, each section formed on-an arc ofslightly greater radius than that of the cylinder, so that the complete ring is slightly elliptical with the long axis between the rabbeted ends.

4. A piston ring composed of similar sec v tionsrabbeted to lap at their ends, each section formed on an arc of slightly greater radius than that of the cylinder, so that the complete ring is slightly elliptical with the long axis between the rabbeted ends, and with the ends of the long axis midway of the rabbets.

5. A piston ring of oval contour having an external circumference corresponding to the lnternal circumference of the cylinder for which it is designed, said ring composed of similar sections lapping at the ends of th long axis of the-completed rings 6. A PlStOIl, ring composed of similar sections lapping at their ends, said ring having an external circumference corresponding in JAMES J. HOWARD. 

